You need to get 50 frags to craft it and you cant upgrade it if you get more so dont buy more than 50 (and would be best to wait for the events to buy the fragments).
Bonus is +285 life and +200 defense. It works the same way as Battle Armor does.

There's a sneek peek of it:
http://forum.naruto.oasgames.com/en/data/attachment/forum/201610/14/025744cbaz49ay94pymv9o.jpg